Operating system: Microsoft Windows 7
GPU: ASUS Strix Radeon Vega 64 Divider version: 19.4.1
CPU: Intel(R) Core(TM) i7-5960X
RAM: 32.0 GB
Broken: 2.80, blender-2.80.0-git.9efe117535c6-windows64
Short description of error
The Quit dialogue jumps around when moved.
Exact steps for others to reproduce the error
If you drag the dialogue around, then move your mouse over or around it you should see it move back to the centre of the UI.